Little biographical detail is known about R. Moshe, but his influence has been incalculable. Most of his relatively short life was spent in Safed, but his sublime personality, powerful intellect and prolific literary output were felt in the entire Jewish world.
He was a beloved disciple of R. Yosef Caro who in his collected Responsa included two by R. Moshe, commenting on one of them. This judge has penetrated to the depths of the law. R. Moshe was one of the four who received semicha from R. Yosef Berab. He served as Rosh Yeshiva and as judge. But, his fame rests on his contribution to Kabbalistic literature and thought.
Although he did not begin studying Kabbalah seriously until he was 20, by the age of 27 he already completed one of the monumental classics of the Kabbalah. Pardes Rimonim, a synthesis of all the major topics in the field, divided into thirty two gates. His chief mentor was his brother-in-law, R. Shlomo Alkabez, the famed author of Lecha Dodi.
R. Shlomo, R. Moshe, and several other disciples would frequently subject themselves to Banishments (Gerushin), when they would leave their homes and engage in unstructured study of various verses and be granted fresh insights. The theory was that since the shechinah (Divine indwelling) was in galut (exile), one could not fully comprehend Torah without leaving ones home. These study sessions are collected in a volume called Gerushin. One of his most popular works is The Palm Tree of Deborah (Tomer Devorah), which describes how a Jew may imitate his Maker in his daily life. The Sweet Light (Or Neerav) explains the necessity of studying Kabbalah. In this volume R. Moshe criticizes those who study this subject without prior Torah knowledge, pointing out that one must first study Bible, Mishnah, and Gemara before studying Kabbalah.
In his Elimah Rabbati and Shiur Komah, R. Moshe acknowledges the usefulness of philosophy but seeks to demonstrate its inadequacy in solving the problem of the bridge between G-d and the world.
While emphasizing the importance of logical analysis, R. Moshe points out that complete knowledge is only possible with the eyes of the soul which yields the inner sight (HaRiyah Hapnimis).
After the publication of the Pardes Rimonim, many Italian scholars traveled to Safed to study with R. Moshe directly. Paradoxically, R. Moshes magnum opus, Or Yakar (The Precious Light), a comprehensive commentary on the Zohar remained unpublished for 400 years. Publication of this multi-volume work was finally begun in 1962 and completed in 1989.
At R. Moshes funeral the Holy Ari observed a pillar of light and his revered rebbe, R. Yosef Caro exclaimed, Here lies the Ark of the Torah.
Sources: Orthodox Union